title: Fitness cost of Litomosoides sigmodontis filarial infection in mite vectors; implications of infected haematophagous arthropod excretory products in host-vector interactions.
abstract: Filariae are a leading cause of infections which are responsible for serious dermatological, ocular, and vascular lesions. Infective third stage larvae (L3) are transmitted through the bite of a haematophagous vector. Litomosoides sigmodontis is a well-established model of filariasis in the mouse, with the vector being the mite Ornithonyssus bacoti. The aim of the study was to analyse the filarial infection in mites to determine the consequences of filarial infection in the blood-feeding and the reproduction of mites as well as in the regulation of vector-induced inflammation in the mouse skin. Firstly, L3 are unevenly distributed throughout the host population and the majority of the population harbours a moderate infection (1 to 6 L3). Filarial infection does not significantly affect the probing delay for blood feeding. The number of released protonymphs is lower in infected mites but is not correlated with the L3 burden. Finally, induced excreted proteins from infected mites but not from uninfected mites stimulate TNF- α and the neutrophil-chemoattractant KC production by antigen-presenting cells (APCs). Altogether, these results describe the modification of the mite behavior under filarial infection and suggest that the immunomodulatory capacity of the mite may be modified by the presence of the parasite, hindering its defensive ability towards the vertebrate host.
authors.affiliation: UMR 7245 MCAM MNHN CNRS, Muséum National d'Histoire Naturelle, 61 rue Buffon, CP52, 75231 Paris Cedex 05, France ; UMR 5554 ISEM CNRS, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier, France.
authors.forename: Adélaïde
authors.initials: A
authors.lastname: Nieguitsila
authors.forename: Roger
authors.initials: R
authors.lastname: Frutos
authors.forename: Catherine
authors.initials: C
authors.lastname: Moulia
authors.forename: Nathaly
authors.initials: N
authors.lastname: Lhermitte-Vallarino
authors.forename: Odile
authors.initials: O
authors.lastname: Bain
authors.forename: Laurent
authors.initials: L
authors.lastname: Gavotte
authors.forename: Coralie
authors.initials: C
authors.lastname: Martin
mesh_terms: D000818:Animals; D005368:Filariasis / Q000469:parasitology* / Q000473:pathology / Q000635:transmission*; D005370:Filarioidea / Q000235:genetics* / Q000472:pathogenicity; D006790:Host-Parasite Interactions / Q000235:genetics*; D007303:Insect Vectors / Q000469:parasitology; D007814:Larva / Q000472:pathogenicity; D051379:Mice; D008925:Mites / Q000469:parasitology